How to Find out Descriptions of Class

Sometimes, we need to get informations about the class which we imported at top of Jupyter Notebook. In this case, you may want to know what properties there are and how methods work. Fortunately, there are some solutions.

To get a list of properties and methods

# I want to know all properties and methods.

import pandas

dir(pandas)

And then, you can get a list of properties and methods, and that is sorted by alphbetical order.

['BooleanDtype',
 'Categorical',
 'CategoricalDtype',
 'CategoricalIndex',
 'DataFrame',
...]

To get the description of the property or the method

# I need the description of DataFrame method.

import pandas

help(pandas.DataFrame)

And then, you can get the descriptions of the method about Parameters, Returns, Examples.

Help on class DataFrame in module pandas.core.frame:

class DataFrame(pandas.core.generic.NDFrame, pandas.core.arraylike.OpsMixin)
 |  DataFrame(data=None, index: 'Axes | None' = None, columns: 'Axes | None' = None, dtype: 'Dtype | None' = None, copy: 'bool | None' = None)
 |  
 |  Two-dimensional, size-mutable, potentially heterogeneous tabular data.
 |  
 |  Data structure also contains labeled axes (rows and columns).
 |  Arithmetic operations align on both row and column labels. Can be
 |  thought of as a dict-like container for Series objects. The primary
 |  pandas data structure.
 |  
 |  Parameters
 |  ----------
 |  data : ndarray (structured or homogeneous), Iterable, dict, or DataFrame
 |      Dict can contain Series, arrays, constants, dataclass or list-like objects. If
 |      data is a dict, column order follows insertion-order.
 |  
 |      .. versionchanged:: 0.25.0
 |         If data is a list of dicts, column order follows insertion-order.
 |  
 |  index : Index or array-like
 |      Index to use for resulting frame. Will default to RangeIndex if
 |      no indexing information part of input data and no index provided.
 |  columns : Index or array-like
 |      Column labels to use for resulting frame when data does not have them,
 |      defaulting to RangeIndex(0, 1, 2, ..., n). If data contains column labels,
 |      will perform column selection instead.
 |  dtype : dtype, default None
 |      Data type to force. Only a single dtype is allowed. If None, infer.
 |  copy : bool or None, default None
 |      Copy data from inputs.
 |      For dict data, the default of None behaves like ``copy=True``.  For DataFrame
 |      or 2d ndarray input, the default of None behaves like ``copy=False``.
 |  
 |      .. versionchanged:: 1.3.0
 |  
 |  See Also
 |  --------
 |  DataFrame.from_records : Constructor from tuples, also record arrays.
 |  DataFrame.from_dict : From dicts of Series, arrays, or dicts.
 |  read_csv : Read a comma-separated values (csv) file into DataFrame.
 |  read_table : Read general delimited file into DataFrame.
 |  read_clipboard : Read text from clipboard into DataFrame.
 |  
 |  Examples
 |  --------
 |  Constructing DataFrame from a dictionary.
 |  
 |  >>> d = {'col1': [1, 2], 'col2': [3, 4]}
 |  >>> df = pd.DataFrame(data=d)
 |  >>> df
 |     col1  col2
 |  0     1     3
 |  1     2     4
 ...