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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def make_dynamic_fields(pattern_module, dynamic_field_patterns, attrs):
 """Add some Salesforce fields from a pattern_module models.py Parameters: pattern_module: Module where to search additional fields settings. It is an imported module created by introspection (inspectdb), usually named `models_template.py`. (You will probably not add it to version control for you because the diffs are frequent and huge.) dynamic_field_patterns: List of regular expression for Salesforce field names that should be included automatically into the model. attrs: Input/Output dictionary of model attributes. (no need to worry, added automatically) The patterns are applied sequentionally. If the pattern starts with "-" then the matched names are excluded. The search stops after the first match. A normal field that exists directly in a class is never rewritten by a dynamic field.. All ForeingKey fields should be created explicitely. (For now to prevent possible issues and also for better readibility of the model. The automatic "dynamic" fields are intended especially for "maybe can be useful" fields and will work with ForeignKey in simple cases, e.g. without Proxy models etc. Works good for me.) This is useful for development: Many fields or all fields can be easily accessed by the model without a huge code. Finally all wildcard fields except the explicit names can be removed when the development is ready or . If you create migrations, you probably want to disable "dynamic_field_patterns" by setting them empty. Example: Meta: db_table = 'Contact' dynamic_patterns = exported.models, ['Last', '.*Date$'] """

    # pylint:disable=invalid-name,too-many-branches,too-many-locals
    import re
    attr_meta = attrs['Meta']
    db_table = getattr(attr_meta, 'db_table', None)
    if not db_table:
        raise RuntimeError('The "db_table" must be set in Meta if "dynamic_field_patterns" is used.')
    is_custom_model = getattr(attr_meta, 'custom', False)

    patterns = []
    for pat in dynamic_field_patterns:
        enabled = True
        if pat.startswith('-'):
            enabled = False
            pat = pat[1:]
        patterns.append((enabled, re.compile(r'^(?:{})$'.format(pat), re.I)))

    used_columns = []
    for name, attr in attrs.items():
        if isinstance(attr, SfField):
            field = attr
            if field.sf_custom is None and is_custom_model:
                field.sf_custom = True
            if not field.name:
                field.name = name
            attname, column = field.get_attname_column()  # pylint:disable=unused-variable
            used_columns.append(column)

    if not pattern_module:
        raise RuntimeError("a pattern_module is required for dynamic fields.")
    for name, obj in vars(pattern_module).items():
        if not name.startswith('_') and isclass(obj) and issubclass(obj, ModelTemplate):
            default_table = obj.__name__
            if getattr(getattr(obj, 'Meta', None), 'db_table', default_table) == db_table:
                cls = obj
                break
    else:
        # not found db_table model, but decide between warning or exception
        if any(not x.startswith('__') for x in dir(pattern_module)):
            raise RuntimeError("No Model for table '%s' found in the module '%s'"
                               % (db_table, pattern_module.__name__))
        warnings.warn("The module '%s' is empty. (It is OK if you are "
                      "rewriting new Models by pipe from inspectdb command.)"
                      % pattern_module.__name__)
        return
    lazy_fields = [(name, obj) for name, obj in vars(cls).items()
                   if isinstance(obj, LazyField) and issubclass(obj.klass, SfField)
                   ]
    for name, obj in sorted(lazy_fields, key=lambda name_obj: name_obj[1].counter):
        for enabled, pat in patterns:
            if pat.match(name):
                break
        else:
            enabled = False
        if enabled:
            if issubclass(obj.klass, ForeignKey):
                to = obj.kw['to']
                if isclass(to) and issubclass(to, ModelTemplate):
                    obj.kw['to'] = to.__name__
            field = obj.create()
            attrs[name] = field
    assert pattern_module